Due to the increasing importance of photocatalysts in the treatment of industrial effluents, in this study, Ag doped TiO2-CuO (TCA) composite nanoparticles were synthesized by sol-gel method. Tetra butylorthotitanate (TBT), copper (II) nitrate trihydrateas, silver nitrate was used as a precursor to titanium dioxide, copper oxide, and silver respectively. Ethanol was used as a solvent. X-ray diffraction (XRD), UV-Vis spectroscopy, nitrogen adsorption-desorption isotherm (BET-BJH), field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM) were used to characterize the nanoparticles. The synthesized photocatalytic nanoparticles have been used to degrade the methylene blue dye solution as a model of organic pollutant under UV and Visible light irradiation. The particle size of TCA-550 sample (highest percentage of photocatalytic degradation under visible light = 43.95%) was about 21-35 nm and the particle size of TCA-650 sample (highest percentage of photocatalytic degradation under UV light = 59.64%) was 39-60 nm. According to the XPS study, the element Ti was predominantly chemically present as Ti4+. Ag was found to be a cation with a capacity of one (Ag+).
